Apparatus for filling powdered or granular materials into bags



Nov; 13, 1956 N. s. STAFFORD ET AL 2,770,439

APPARATUS FOR FILLING POWDERED 0R GRANULAR MATERIALS INTO BAGS FiledSept. 17, 1954 4 Sheets-Sheet 1 F rllltlr' O K A 4 O .f B 6 4 3 ZJ m m25 a n W A i A 2 6 n O 5 9 4 i 3 2 A awww A m s swarm 4 z I s mm .4 123mwin-F 02 a a A w .5% O I l 10 I.

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T INVENTORS I E l NEIL s STAFFORD I ozone: A WORLEY av '5,

A ATTORNEY Nov. 13, 1956 N. s. STAFFORD ET AL 2,770,439

APPARATUS FOR FILLING POWDERED OR GRANULAR MATERIALS INTO BAGS FiledSept. 17, 1954 4 Sheets-Sheet 2 INVENTORS NEIL S. STAFFORD GEORGE A.WORLEY ATTORNEY Nov. 13,- 1956 N. s. STAFFORD ET AL 2,770,439

APPARATUS FOR FILLING POWDERED OR GRANULAR MATERIALS INTO BAGS FiledSept. 17, 1954 4 Sheets-Sheet 3 INVENTORS ATTORNEY FII3 E| NEIL s.STAFFORD GEORGE A.WORLEY Nov. 13, 1956 N. s. STAFFORD ET AL 2,770,439APPARATUS FOR FILLING POWDERED 0R GRANULAR MATERIALS INTO BAGS FiledSept. 17, 1954 4 Sheets-Sheet 4 P'II3 '7 INVENTORS NEIL S. STAFFORDGEORGE A.WORLEY ATTORNEY United States Patent APPARATUS FOR FILLINGPOWDERED OR GRANULAR MATERIALS INTO BAGS Neil S. Stafford, San Jose, andGeorge A. Worley, Newark,

alif., assignors to Food Machinery and Chemical Corporation, San Jose,Calif., a corporation of Delaware Application September 17, 1954, SerialNo. 456,768

6 Claims. (Cl. 249-60) The present invention relates to apparatus forfilling powdered or granular materials into bags. More particularly, thepresent invention relates to apparatus, of the type referred to, whichemploy aeration of the powdered gr granular material to facilitatedelivery thereof into the ags.

Apparatus of this type comprise usually a tank of substantial heightwherein the powdered or granular materials are placed into afluid-condition with currents of air or other gaseous flnidizing media,a discharge spout at the lower end of said tank over which the fillingsnout of the bag is engaged and through which the fluidized mass ofpowdered or granular material flows into the bag, control mechanism bymeans of which the spout may be opened or closed, and a weighingmechanism which supports the bag in material-receiving position andwhich is arranged to cause the spout control mechanism to block furtherflow of the material Whenever a predetermined quantity of the materialhas been filled into the bag.

It is an object of the present invention to provide a discharge spout,for bag filling apparatus, comprising control mechanism that is operableto block rapidly the discharge of fluidized material through said spout.

Another object is to provide a spout control mechanism that is of simpleconstruction yet rapid and dependable in operation.

Another object is to provide a flow control valve for powdered materialsthat comprises a flexible tube and means for pinching the tube for thepurpose of stopping flow of the fluidized material therethrough.

Another object is to provide a flexible tube for a valve, of the typereferred to, that may readily be pinched off without placing harmfulstrains on its walls.

Another object is to provide a simple and etfective supporting structurefor the bags while they are being filled.

Another object is to provide a simple and effective supporting frame formounting the spout and the spout control mechanism, and for the supportof the bags to be filled.

Another object is to provide a supporting structure for the bags to befilled that holds the bags securely in position while they are filled,and which may be operated to release the bags for automatic dischargeupon completion of the filling operation.

These and other objects of the present invention will be apparent fromthe following description of the accompanying drawings which illustratea preferred embodiment thereof and wherein:

Fig. l is a fragmentary perspective of a bag filling machine embodyingthe invention.

Figs. 2 and 3 are longitudinal sections through the spout and the spoutcontrol mechanism of the machine illustrated in Fig. 1 showing diflerentoperational positions thereof.

Figs. 4 and 5 are front elevations, partly in section, of the spout andthe spout control mechanism in the operational portions illustrated inFigs. 2 and 3.

Fig. 6 is a side elevation of the bag supporting mecha- "ice nism of theapparatus shown in Fig. 1 showing a filled bag in the process of beingdischarged therefrom.

Figs. 7 and 8 are combined hydraulic and electric circuit diagramsrepresenting different operational positions of the spout controlmechanism.

In Fig. 1 the reference numeral 10 indicates the bottom end of a tank 10which rests upon a suitable pedestal 12. In said tank a supply ofpowdered or granular material is maintained in fluid like conditions ina well known manner by rising currents of air, the necessary quantity ofair being delivered into the tank near the bottom end thereof through asuitable conduit 14. In the illustrated apparatus, the lower section 16of the front wall 18 of tank 10 is forwardly tilted and has a dischargeopening 20 (Figs. 2 and 3) through which the material may enter into aninclined spout structure 22. Said spout structure is composed of aninitial portion 24 which is made of resilient material, and a terminalportion 26 which is made of rigid material and which for-ms the actualspout over which the receiving snout of the bag to be filled is engaged.

Portion 24 of the spout structure is formed by a short rubber hose whoseopposite ends are extended into annular flanges 28 and 30, respectively.Through flange 28 the hose 24 is suitably bolted to the forwardly tiltedwall section 16 of tank 10 around the discharge opening 24) thereof, asillustrated in Figs. 2 and 4. The other flange 30 of said hose issecured by bolts 31 to an annular disk 32 that forms a part of a bagsupporting frame 34, which is suspended from one arm of a scale 36 thatis located in front of and below the tank 10. Secured to the oppositeface of the annular disk 32 by the same bolts 31 that secure theflexible hose 24 to said disk, is the flanged end 49 of the actual spout26, which may be made from steel, and which forms a downwardly directeddischarge opening 42, as best shown in Fig. 2.

Associated with the spout 26 is a clamping mechanism 44 that may bemanipulated to hold the receiving snout of a bag securely in engagementwith the spout, as shown in Fig. 1. Said mechanism comprises the actualclamp 46 which has the formof a. shell segment of horseshoe-shaped crosssection. Secured to the converging sides of said shell segment arerectangular rubber pads 48a and 4812 that project downwardly below thelinear edges of said clamp segment and which are intended to engage thebag that is to be held on the spout. The shell segment 46 has a tail 50that turns on a spindle 52 which extends transversely across thespoutand which is held in and between a pair of vertically disposedtriangular shelves 54a and 54b. The shelves in turn are secured to, andproject forwardly from, an upwardly directed bar-shaped extension of theannular disk 32. Springs 56a and 56b tensioned between the shelves 540,54band studs 58a, 58b, respectively, that project laterally from thetail 50 of the clamp near the shell portion 46 thereof, urgethe clamp inclockwise direction, as viewed in Figs. 2 and 3, into a position whereinit is withdrawn from the spout so that the snout of a bag may be readilyslipped over the spout.

Means are provided that may be manipulated to force to clamp with itsrubber pads 48a and 48b over and into engagement with the snout of a bagon the spout so as to retain the bag in material-receiving positionthereon. For this purpose a horizontal spindle 60 is rotatably supportedin the crest points of the two aforementioned triangular shelves 54a and54b above the juncture of the tail 52 and the shell segment 46 of theclamp. Rigidly secured to one laterally projecting end of said spindleis a downwardly extending operating handle .62. Likewise secured to saidspindle 60 intermediately of the shelves 54a and 54b is a depending arm64 which carries at its free end a roller :66 that engages the back ofthe clamp. When the arm 64 is in the counterclockwise positionillustrated ,in Fig. 3, wherein its roller 66 rides over the tail 52 ofthe clamp, the springs 56a and 56b are permitted to raise the clamp intoa position wherein it is withdrawn from the spout. When the spindle 60is turned in clockwise position by raising the handle 62, however, theroller 66 depresses the clamp and forces the rubber pads 48a and 48b ofits shell portion into engagement with the snout of a bag that may havebeen slipped over the spout 26, thus holding the snout of the bagsecurely against the flanks of the spout (Fig. 2).

The arm 64 and the clamp 46-52 in conjunction with the springs 56a and56b form, in fact, a toggle, and when the operating handle 62 is raisedto an extent Where the roller 66 on arm 64 has passed the planedetermined by spindle 6t) and the studs 58a and 58b at which the springs56a and 56b engage the clamp, said springs will actually urge the arm 64in clockwise direction as viewed in Figs. 2 and 3. To avoid excessiveclockwise rotation of arm 64 which would withdraw the roller 66 from theclamp, the spindle 60 carries firmly secured thereto another arm 68 thatis provided at its free end with an adjustable contact stud 70. Saidstud carries a metal disc 71 that is arranged to strike against the topedge of shelf 54a whenever the clamp has reached its position of closestapproach to the spout. Thus, the clamp once brought down upon the snoutof a bag engaged over the spout, remains dependably in bag retainingposition until an operator lowers the handle 62 to its originaldownwardly extending position. When the clamp is in its bag retainingposition, the contact stud 70 engages and depresses the actuating button72 of a normally open switch 74 that lies in the power circuit of asolenoid 76. Said solenoid 76 controls the position of a pneumatic valve78 which is supported from the front wall 18 of the tank and which inturn controls the supply of air from a source of compressed air (notshown) to a pneumatic cylinder 80. The cylinder is mounted upon acrescent-shaped mounting channel 81 secured by an arm 82 to theforwardly tilted section 16 of the tank wall 18, and said cylinderdetermines the positionof the mechanism that opens or closes theflexible hose 24, as will presently be described.

In accordance with the invention, mechanism is provided that holds theresilient hose 2 4 normally in the pinched or squeezed conditionillustrated in Figs. 3 and 5 to block flow of the fluidized materialtherethrough, and which may be operated to release the flexible hose 24temporarily to permit flow of the material therethrough. Said mechanismcomprises a pair of horizontally disposed rods 83 and 84 arranged aboveand below the resilient hose 24, that are normally held so close to eachother as to squeeze the hose between them, and which may be withdrawnfrom said hose to permit it to reexpand and form a conduit for thepassage of a fluidized material therethrough. To this end the upper rod83 is rigidly attached to the normally downwardly projected piston rod86 of the hereinbefore mentioned pneumatic cylinder 80, and thecrescent-shaped mounting channel 81 journals in its opposite pointsequi-armed bellcranks 92a and 92b, respectively. Relatively short twinlinks 94a and 94b pivotally connect intermediate points of the upperpinching rod 83 to the inner ends of said bellcranks, while elongatedtwin links 96a and 96b connect the outer ends of said bellcranks to theouter ends of the lower pinching rod 84. Whenever the piston rod 86 ofthe hydraulic cylinder 80 is downwardly projected and pushes the upperpinching rod 83 into engagement with the resilient hose 24, asillustrated in Figs. 3 and 5, the bellcranks 92a and 92b are in therotary position illustrated in Fig. 5, wherein their outer ends areraised. In this condition, they hold the lower pinching rod 84 throughthe links 96a and 96b in engagement with the resilient hose 24, so thatthe hose is completely closed, as illustrated in Fig. 5. When thecylinder 80 is operated to retract its piston rod 86, it withdraws theupper pinching rod 83 from the hose 24 and swings the bellcranks 92a and92b in counter-clockwise and clockwise direction, respectively. Thislowers their outer ends which is effective to withdraw the lowerpinching rod 84 from the hose 24, permitting it to open fully under itsown resiliency, as illustrated in Fig. 4. To prevent wobbling of thelower pinching rod during the described operation, guide bars 97a and97b rigidly secured to and depending vertically from the opposite endsof the upper pinching rod 83 are engaged, and slide, between theindividual members of the elongated twin links 960: and 96b, as bestshown in Figs. 4 and 5.

To minimize the strain imposed upon the rubber hose 24 by the continualoperation of the described pinching mechanism, and thus delay itsdeterioration, it would be desirable to make said hose relatively longsince the continual deformation of its walls would in this manner bedistributed over a relatively large area. However, fluidized materialwhen escaping from the fluidizing tank through a discharge conduit,deaerates rapidly and loses the characteristics of a liquid. For thisreason it would be desirable to make such discharge conduits as short aspossible to assure free flow of the material from the fluidizing tankinto the bag. In accordance with the invention I provide a hoseconstruction for spouts, of the type referred to, that may be held asshort as the mechanical dimensions of the pinching mechanisms willpermit, and which yet will not be subjected to excessive deteriorationby operation of the described pinching mechanism. Having reference toFigs. 2 and 3, the resilient hose 24 is formed with bellows-like folds180 and 192 at either side of the smooth portion 98 that is engaged bythe pinching rods 83 and 84. By virtue of said folds the strain imposedupon the walls of the hose, as it is deformed by the pinching rods, isnegligible and, though short in length, a resilient hose constructed asdescribed and illustrated, will last for extended periods of practicaluse without appreciable signs of deterioration.

The hereinbefore mentioned supporting structure 34 for the bag comprisesa substantially vertically disposed post 184 whose upper end 106 is bentto slant in parallelism with the forwardly tilted wall section 16 oftank 10. Rigidly secured to said slanted upper end 106 of post 104 is adownwardly directed bar-shaped extension 108 of the hereinbeforementioned annular disk 32 to which the spout 26 and the hose 24 aresecured, as previously described. Thus, the annular disk 34 is likewisedisposed in a plane parallel to the forwardly tilted wall section 16,and the center axis of the discharge conduit formed by hose 24 and spout26 extends at right angles to said plane and hence slants downwardly.

Directly below its bend line the post 104 carries firmly secured theretotwo symmetrically opposed L-shaped arms 110a and 110b, the free ends ofwhich are supported for limited rotational movement from the free endsof a U-shaped stirrup 112 that embraces said post and its L-shaped arms.The stirrup 112 constitutes part of the hereinbefore mentioned scale 36.Its side bars 114a and 114b possess at intermediate points laterallyprojecting ears 116a and 116b, respectively, that rest upon upwardlydirected knife edges 118 (only one being visible in Figure 1) which aresuitably mounted in and project upwardly from two horizontally disposedparallel girders 120a and 12% of the pedestal 12. A counterweight 122 isadjustably engaged over a threaded rod 124 that projects rearwardly fromthe connecting bar 126 of the U-shaped stirrup 112.

Due to the presence of the counterweight 122 the U- shaped stirrup 112is normally tilted rearwardly on the knife blades 118 to an extentwherein a lug 128 mounted upon and projecting laterally from the crossbar 126 of stirrup 112, bears down upon and depresses the actuatingbutton 130 of a normally open switch 132 that is mounted upon theadjacent girder 120b. Said switch 132 lies in the hereinbefore mentionedpower circuit of the solenoid 76 that controls the position of thepneumatic valve 78,

and its significance in the operation of the bag filling machineembodying the present invention will be described in greater detailhereinafter.

At its lower end the post 104 carries an adjustable saddle 133 uponwhich the bags are supported during the filling operation. Said saddlecomprises a rectangular sleeve 134 that is slidably received over thelower end of post 104 and which may be secured to said post at a varietyof 'dilferent levels, depending upon the size of the bag to be filled,by means of a removable pin 136 that engages an aperture in said sleeve,and may selectively be engaged into any one of a plurality of verticallyspaced apertures 138 provided in the lower end of said post. The sleeve134 carries rigidly a forwardly projecting stud 140 within the free endof which is pivotally supported a U-shaped stirrup 142 whose upwardlydirected parallel legs 144a and 14411 mount forwardly projecting bars146a and 146b, respectively. The ends of the saddle bars 146:: and 146b,remote from post 104, are curved downwardly as shown in Fig. 1, andsprings 143a and 148b tensioned between the opposite ends of said barsadjacent the post 104 and studs 150 projecting laterally from the bottomend of sleeve 134 urge said bars into the position illustrated in Fig. 1wherein they come to rest upon the opposite ends of a cross bar 151 thatis rigidly secured to the sleeve 134. In this position the saddle bars146a and 14617 are substantially horizontally disposed. The saddle bars146a and 14617 are spaced from each other by a distance suflicient toreceive a collapsed bag therebetween, yet they are sufliciently close toeach other to permit the lower end of a bag as it is filled withmaterial from tank 10, to spread over and rest upon their horizontalruns. A buffer link 153 may be interposed between the post 104 and across-brace 155 of pedestal 12 below the level of the knife edges 118 toprevent excessive rotation of said post 104 during manipulation of a bagon saddle 133 which may harmfully stretch the flexible hose portion 24of the spout structure 22.

When there is no bag upon the described bag supporting structure, theweight switch 132 in the power circuit of the valve control solenoid 76is closed due to the elfect of the adjustable counterweight 122 on theposition of the stirrup 112, as previously described. The clamp operatedswitch 74 in said same power circuit, however, is open so that the valvecontrol solenoid 76 is -de-energized. When said solenoid isde-energized, a spring 154 in the valve 78 maintains said valve in theposition illustrated in Fig. 8, wherein compressed air is directed intothe pneumatic cylinder 80 above its piston 156 and the space below thepiston 156 is connected to the outside. Under such conditions the forceof the air above the piston and a strong spring 152 within the pneumaticcylinder 80 hold the piston in a position wherein the piston rod isdownwardly projected and causes the pinching rods 83 and 84 to closeupon the resilient hose 24 preventing escape of any fluidized materialfrom the tank to the outside.

In practice the operator may now place an empty bag into the spacebetween the saddle bars 146a and 1461) at the lower end of post 104 andbetween the L-shaped arms 110a and 11012, and engage its snout over thespout 26. He then manipulates the handle 62 to close the clamp 44 fullyupon the snout of the bag and the spout underneath so that the bag issecurely held in engagement with the spout. As soon as the clamp 44 isfully engaged over the snout of the bag, the arm 68 on the operatingspindle 60 of the clamp control mechanism brings the adjustable contactstud 70 against the operating button 72 of the normally open switch 74in the power circuit of the valve control solenoid 7 6 and causes saidswitch to close. This completes the power circuit through the valvecontrol solenoid 76 and causes energization of said solenoid.Energization of the solenoid 76 moves the control valve 78 into theposition illustrated in Fig. 7, wherein the source of compressed air isconnected to the cylinder space below the piston 156 while the cylinderspace above the piston is connected to the outside atmosphere. As aresult thereof, the piston rod is retracted against the urgency ofspring 152, the pinching rods 83 and 84 are withdrawn from the resilienthose 24 of the spout and said hose is allowed to expand (Figs. 2 and 4).Fluidized material may now flow through the spout under the weight ofthe fluidized column within the tank 10 and fill the bag upon the saddle133; and as the bag is filled, its lower end begins to bulge, and risesabove and spreads over the bars 146:: and 146mb of the supporting saddleso that it rests fully upon said bars.

As soon as the quantity of the material accumulating in the bag reachesa desired limit, which may be predetermined by adjustment of thecounterweight 122 upon rod 124, the scale stirrup 112 tilts upon theknife edges 118 from its reclining to a forwardly declined position, andthe actuating lug 128 on its connecting bar 126 releases the actuatingbutton 130 of the scale switch 132 causing said switch to open. Thisinterrupts the power circuit of the valve control solenoid 76. Theresultant deenergization of said solenoid permits the valve to return tothe position illustrated in Fig. 8 wherein it connects the cylinderspace below the piston 156 to the outside atmosphere, while connectingthe source of compressed air to the cylinder space above said piston.This, in conjunction with the force of spring 152, causes an extremelyrapid projection of the piston rod which eflects almost instantaneousclosure of the pinching bars 83 and 84 upon the resilient hose 24 of thespout structure. Thus, further supply of powdered or granular materialinto the bag upon the saddle 133 ceases almost instantaneously when thebag reaches its proper weight.

The bag may now be released by proper manipulation of the clamp controlhandle 62, and as soon as the clamp is withdrawn from its snout, it willslide off from the spout due to the inclined disposition thereof. Whenthis occurs, the supporting bars 146a and 14612 of saddle 133 tiltagainst the urgency of springs 148a and 14% under the weight of thefilled bag, since its center of gravity is located above the downwardlycurved unsupported ends of said bars at a point further removed from thepost 104 than the pivotal support of said bars in stud 140. The filledbag will, therefore, slide forwardly oil": from the saddle bars asillustrated in Fig. 6, and drop on a conveyor or trolley (not shown),with the L-shaped arms a and 11012 of post 104 acting to preventaccidental discharge of the bag in a lateral direction.

As soon as the filled bag has slipped off the supporting structure 34,the counterweight 122 returns the scale stirrups 112 to the rearwardlyinclined position wherein the lug 128 bears against the actuating buttonof the weight switch 132 and closes said switch (Fig. 7). Thus, themechanism is again in condition for commencement of operation as soon asthe clamp 44 is closed over the receiving snout of another bag.

It should here be noted that the described arrangement is such thatthere can never be an uncontrolled discharge of fluidized materialthrough the spout, irrespective of whether there is failure in theelectric power that controls the pneumatic valve or in the supply ofcompressed air. If there should be a power failure, the solenoid 76deenergizes immediately, or remains de-energized, as the case may be,causing the valve 78 to resume, or to remain in, the positionillustrated in Fig. 7, wherein the spring 152 holds the piston rod ofthe pneumatic cylinder 80 in projected position, which is effective toclose the spout. Similarly, if the supply of compressed air should fail,the spring 152 returns the piston rod to its projected position, orholds it in said position as the case may be, so that the spout willclose or remain closed, preventing any uncontrolled escape of thefluidized material from tank 10.

While We have described our invention with the aid of an exemplaryembodiment thereof, it will be understood that we do not wish to belimited to the specific constructional details shown and described,which may be departed from without departing from the scope and spiritof my invention.

When fiuidization of granular or powdered materials is referred to inthe above given description and in the following claims, this term isintended to mean not only full fluidization of the said materials,wherein they behave entirely as a liquid, but also all those conditionsof lesser aeration which reduce their natural angle of repose and willtherefore permit said materials to flow down inclined surfaces thatslant at angles less than their natural angle of repose.

We claim:

1. A discharge spout for fluidized solids comprising an initial conduitportion of resilient material and a terminal conduit portion of rigidmaterial, said initial conduit portion having a section formed in themanner of a bellows and a smooth section, opposed members at either sideof said smooth section normally held in a position sufficiently close toeach other to deform said smooth section and block the flow of fluidizedsolids therethrough, a clamp movable into a position wherein it iseffective to hold a bag in receiving position with regard to saidterminal conduit portion, and means operative in response to movement ofsaid clamp into bag holding position to withdraw said opposed membersfrom said smooth section and thus permit flow of fluidized solidsthrough said spout.

2. A discharge spout for fluidized solids comprising an initial conduitportion of resilient material and a terminal conduit portion of rigidmaterial, said initial conduit portion having a pair of axially spacedsections formed in the manner of a bellows and intermediately thereof asmooth section, opposed members at either side of said smooth sectionnormally held in a position sufliciently close to each other to deformsaid smooth section and block the flow of fluidized solids therethrough,a clamp movable into a position wherein it is effective to hold a bag inreceiving position with regard to said terminal conduit portion, andmeans operative in response to movement of said clamp into bag holdingposition to withdraw said opposed members from said smooth section andthus permit flow of fluidized solids therethrough.

3. In a machine for filling bags with powdered or granular materialhaving a material supply tank, means for fluidizing the material in thetank, a discharge spout, a conduit leading from said tank to said spoutand a scale; a supporting structure for the bag to be filled comprisinga substantially vertically disposed post, means pivotally supportingsaid post at a point intermediately of its ends from one side of thescale, an annular disc or rigidly mounting the discharge spout in adeclining position at the upper end of said post, a support for the bagpivotally supported from the lower end of said post, and releasablemeans supported above said annular disc for clamping thematerial-receiving snout of a bag onto the spout.

4. In a machine for filling bags with powdered or granular materialhaving a material supply tank, a discharge spout, a conduit leading fromsaid tank to said spout and a scale; a supporting structure for the bagto be filled comprising a substantially vertically disposed post, meanspivotally supporting said post at a point intermediately of its endsfrom one side of the scale, an

annular disc for rigidly mounting the discharge spout in a decliningposition at the upper end of said post, a support for the bag includinga pair of substantially horizontally extending parallel bars formovement about a transverse horizontal axis, means pivotally supportingsaid bars from the lower end of said post at a point in front of saidpost yet closer to said post than the center of gravity of a filled bagresting thereon, and releasable means supported from the upper end ofsaid post above the spout for holding the material receiving snout of abag onto the spout.

5. In a machine for filling bags with powdered or granular materialhaving a material supply tank, a discharge spout, a conduit leading fromsaid tank to said spout and a scale; a supporting structure for the bagto be filled comprising a substantially vertically disposed post, meanspivotally supporting said post at a point intermediately of its endsfrom one side of the scale, an annular disc at the upper end of saidpost for rigidly mounting the discharge spout in a declining position, asupport for the bag including a pair of substantially horizontallyextending bars having downwardly curved outer ends, said bars beingspaced transversely at a distance sufiiciently wide to receive the lowerend of an empty bag therebetween, but sufliciently close to cause thelower end of a filled bag to spread over and rest on said bars, meanspivotally supporting said bars from the lower end of said post at apoint closer to said post than the center of gravity of a filled bagresting thereon, and releasable means supported from the upper end ofsaid post above said annular disc for holding the materialreceivingsnout of a bag onto said spout.

6. For a bag filling machine having a fluidizing tank, a discharge spoutat the lower end of said tank, a conduit leading from said tank to saidspout, and a scale; a supporting structure for the bags to be filledcomprising a substantially vertically disposed post, means at the upperend of said post for rigidly attaching the spout thereto, substantiallyhorizontal bars pivotally supported from the lower end of said post fortilting movement under the weight of a filled bag into a positionwherein they slant downwardly away from said post, spring meansyieldably holding said bars in their horizontal bag supporting position,releasable means for holding a bag resting upon said bars with itsmaterial-receiving snout in engagement with said spout, and a pair ofL-shaped arms rigidly supported from said post at an intermediate pointthereof to form lateral guides for a bag supported on said bars toconfine movement thereof upon release of said holding means to the planeof rotation of said tilting bars, the free ends of said arms beingpivotally supported from one side of said scale.

References Cited in the file of this patent UNITED STATES PATENTS2,183,835 Foulke Dec. 19, 1939 2,317,865 Talbot Apr. 27, 1943 2,371,434Eppler Mar. 13, 1945 FOREIGN PATENTS 503,351 Great Britain Apr. 5, 19391,056,327 France Feb. 25, 1954

